Collaborative Research: Global Aspects of Tropical Cyclogenesis

合作研究：热带气旋发生的全球方面

• 批准号: 0630721
• 负责人: David Nolan
• 金额: $ 21.16万
• 依托单位: University of Miami
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-10-01 至 2009-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0630721&HistoricalAwards=false
• 关键词: Collaborative; Research; Global; Aspects; Tropical

Tropical cyclones (hurricanes) do not appear spontaneously in the tropical atmosphere; instead they must be triggered by a preexisting disturbance. It is hypothesized that these storms are subcritical instabilities of the tropical atmosphere. This implies that the strength of the disturbance necessary to trigger a hurricane depends on the background state of the tropical atmosphere and ocean, and that, at least in theory, hurricanes could appear spontaneously in a different climate, one with instability parameters that exceed a critical point.The hypothesis of subcritical instability will be explored using a high-resolution numerical model to map out the instability diagram for tropical cyclogenesis and to reveal physical processes underlying the structure of this diagram. Physical insights from these experiments, together with observational data and experiments with a more idealized model, will be used to develop and refine a cyclogenesis index. Ultimately such an index can provide information about the frequency with which hurricanes form in different climates.Broader impacts of this research include training a graduate student and a post-doctoral researcher, as well as developing understanding and tools that could lead to improved predictions of how tropical cyclone activity will change as climate changes, either naturally or due to human influence.

热带气旋（飓风）不会在热带大气中自发出现，而是由预先存在的扰动触发。据推测，这些风暴是热带大气的亚临界不稳定性。这意味着引发飓风所需的扰动强度取决于热带大气和海洋的背景状态，至少在理论上，飓风可以在不同的气候中自发出现，一个不稳定参数超过临界点。亚临界不稳定性的假设将使用高-分辨率数值模式绘制热带气旋生成的不稳定图，并揭示该图结构下的物理过程。从这些实验中获得的物理见解，以及观测数据和采用更理想化模型的实验，将用于制定和完善气旋生成指数。这项研究的更广泛影响包括培训一名研究生和一名博士后研究人员，以及发展理解和工具，从而改善对热带气旋活动如何随着气候变化而变化的预测，无论是自然变化还是人为影响。